Estimation of the excess lifetime cancer risk from radon exposure in some buildings of Kufa Technical Institute, Iraq

A number of international health organizations consider the exposure to residential radon as the second main cause of lung cancer after cigarette smoking. It was found that there is no database on radon concentrations for the Kufa Technical Institute buildings in the literature. This therefore triggers a special need for radon measurement in some Kufa Technical Institute buildings. This study aims to investigate the indoor radon levels inside the Kufa Technical Institute buildings for the first time using different radon measurement methods such as active (RAD-7) and passive (LR-115 Type II) methods. Seventy eight of Solid-State Nuclear Track Detectors (SSNTDs) LR-115 Type II were distributed at four buildings within the study area. The LR-115 Type II detectors were exposed in the study area for three months period. In parallel to the latter, seventy two active measurements were conducted using RAD-7 in the same buildings for correlation investigation purposes between the two kinds of measurements (i.e. passive and active).The results demonstrate that the radon concentrations were generally low, ranging from 38.4 to 77.2 Bq/m3, with a mean value of 50 Bq/m3. The mean of the equilibrium equivalent radon concentration and annual effective dose were assessed to be 19.9 Bq/m3 and 1.2 mS/y, respectively; the excess lifetime lung cancer risk was approximately 11.6 per million personal. A high correlation was found between the methods of measurements (i.e. LR-115 Type II and RAD-7), R2 = 0.99 which is significant at P < 0.001. The results of this work revealed that the Radon concentration was below the action level set by the United States Environmental Protection Agency of 148 Bq/m3. This therefore indicates that no radiological health hazard exists. However, the relatively high concentrations in some classrooms can be addressed by the natural ventilation or the classrooms being supplied with suction fans